Multivariate morphometric analysis of taxonomic relationships in Eleocharis tenuis (Cyperaceae)


  • Lane D. Gibbons Department of Biology, James Madison University Herbarium
  • Conley K. McMullen Department of Biology, James Madison University Herbarium



Morphology of Eleocharis tenuis is traditionally recognized as being highly variable and delimited only to the level of variety. However, novel morphometric data indicate that the varieties of E. tenuis are unique and well delimited by four of ten characters examined in this study. Furthermore, these unique morphological entities are supported by correlating cytological data. Herein, we treat E. tenuis var. verrucosa at the rank of species, as E. verrucosa, to reflect the evolutionary significance of this entity. We also provide a key to distinguish E. verrucosa from the remaining varieties of E. tenuis.


Catling, P.M. 1994 Eleocharis compressa × Eleocharis erythropoda, a new natural hybrid spike rush from Ontario. Canad. J. Bot. 72:837–842.

Catling, P.M. & S.G. Hay. 1993. The hybrid origin of Eleocharis macounii. Rhodora 95:85–96.

Edwards, A.L., D.W. Lee, & J.H. Richards. 2003. Responses to a fluctuating environment: Effects of water depth on growth and biomass allocation in Eleocharis cellulosa Torr. (Cyperaceae). Canad. J. Bot. 81:964–975.

González-Elizondo, M. & P.M. Peterson. 1997. A classification of and key to the supraspecific taxa in Eleocharis (Cyperaceae). Taxon 46:433–449.

González-Elizondo, M., P.M. Peterson, & I. Granzow-de La Cerda. 1997. A cladistic and phenetic analysis of the Pauciflorae group of Eleocharis (Cyperaceae). BioLlania Edición Esp. No. 6:341–368.

Gregor, T. 2003. Eleocharis mamillata—distribution and infraspecific differentiation. Folia Geobot. 38:49–64.

Harms, L.J. 1968. Cytotaxonomic studies in Eleocharis subser. Palustres: Central United States taxa. Amer. J. Bot. 55:966–974.

Harms, L.J. 1972. Cytotaxonomy of the Eleocharis tenuis complex. Amer. J. Bot.59:483–487.

Larson, B.M.H. & P.M. Catling. 1996. The separation of Eleocharis obtusa and Eleocharis ovata (Cyperaceae) in eastern Canada. Canad. J. Bot. 74:238–242.

de Queiroz, K. 2007. Species concepts and species delimitation. Syst. Biol. 56:879–886.

Roalson, E.H. & E.A. Friar. 2000. Infrageneric classification of Eleocharis (Cyperaceae) revisited: Evidence from the internal transcribed spacer (ITS) region of nuclear ribosomal DNA. Syst. Bot. 25:323–336.

Roalson, E.H., C.E. Hinchliff, R. Trevisan, & C.R.M. da Silva. 2010. Phylogenetic relationships in Eleocharis (Cyperaceae): C4 photosynthetic origins and patterns of diversification in the spikerushes. Syst. Bot. 35:257–271.

Rosen, D.J., S.L. Hatch, & R. Carter. 2007. Infraspecific taxonomy and nomenclature of Eleocharis acutangula (Cyperaceae). J. Bot. Res. Inst. Texas 1:875–888.

Schuyler, A.E. 1977. Chromosome observations on some eastern North American Eleocharis (Cyperaceae). Brittonia 29:129–133.

Smith, S.G. 2001. Taxonomic innovation in North American Eleocharis (Cyperaceae). Novon 11:241–257.

Smith, S.G. & T. Gregor. 2014. North American distribution of Eleocharis mamillata (Cyperaceae) and confusion with E. macrostachya and E. palustris. Rhodora 116:163–186.

Smith, S.G., J.J. Bruhl, M.S. Gonzalez-Elizondo, & F.J. Menapace. 2002. Eleocharis. In: Flora of North America Editorial Committee, eds. 1993+. Flora of North America north of Mexico, Vol. 23, Magnoliophyta: Commelinidae (in part): Cyperaceae. Oxford University Press, New York and Oxford, U.SA. and UK. Pp. 60–120.

Sorrie, B.A. & R.J. LeBlond. 2014. Eleocharis fallax (Cyperaceae): Recent collections and morphological comparison with E. ambigens and E. monteviensis. Phytoneuron 2014-7:1–7.

Strandhede, S.O. 1967. Eleocharis subser. Eleocharis in North America. Taxonomical comments and chromosome numbers. Bot. Not. 120:355–368.

Svenson, H.K. 1929. Monographic studies in the genus Eleocharis. Rhodora 31:121–135; 167–191.

Svenson, H.K. 1932. Monographic studies in the genus Eleocharis–II. Rhodora 34:193–203; 215–227.

Svenson, H.K. 1947. The group of Eleocharis palustris in North America. Rhodora 49:61–67.

Svenson, H.K. 1953. The Eleocharis obtusa-ovata complex. Rhodora 55:1–6.

Svenson, H.K. 1957. Scirpeae (continuatio). North Amer. Fl. 18:505–556.

Thiers, B. 2016. Index herbariorum: A global directory of public herbaria and associated staff. New York Botanical Garden's Virtual Herbarium.




How to Cite

Gibbons, L. D., & McMullen, C. K. (2019). Multivariate morphometric analysis of taxonomic relationships in Eleocharis tenuis (Cyperaceae). Journal of the Botanical Research Institute of Texas, 13(1), 71–81.